Marine. Svalbard Life 139

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1 Marine mammals A total of 12 species of marine mammals regularly inhabit the Arctic Ocean: 4 species of whales, the polar bear, the walrus, and 6 species of ice-associated seals. Several additional species (e.g. the sperm whale, blue whale, fin whale, humpback whale, killer whale, and harbour porpoise) are spotted either occasionally or regularly within the marginal waters of the Arctic. Despite their distant relationships, all marine mammals share the common attribute of being predators that capture their prey on or in the oceans. All are relatively long lived, and virtually all are critical food resources to the indigenous peoples of the Arctic. This section presents a few of the more common species that may be encountered by visitors to Svalbard. At times, whales become stranded and subsequently die in Svalbard. Such events create the biggest feasts in the Arctic, attracting polar bears, Arctic foxes and numerous gulls, all of which fight to secure a good meal. The photograph shows the remains of a whale that has been consumed by scavengers. During the climax of such feasts, polar bears literally throw themselves into the body cavities of dead whales, and their fur becomes tinted brown with coagulated and dried whale blood. n Svalbard Life 139

2 Marine mammals: Polar bear The Arctic animal par excellence is the polar bear, a bear that is largely native within the Arctic Circle encompassing the Arctic Ocean and its surrounding seas and landmasses. It is the world s largest land carnivore and the largest species of bear, in concert with the omnivorous Kodiak bear, which is approximately the same size. An adult male polar bear weighs around kilograms, whereas an adult female is about half that size. Although the species is closely related to the brown bear, it has evolved to occupy a narrower ecological niche. Body characteristics are adapted for cold temperatures, for moving across snow, ice, and open water, and for hunting seals, which make up most of its diet. Although most polar bears are born on land, they spend most of their time at sea; the term maritime bear derives from this fact. Thus, the polar bear is regarded as a marine mammal. Polar bears hunt their preferred food of seals from the edge of sea ice, often living onshore on fat reserves when no sea ice is present. The preferred habitat is thus the seasonal sea ice covering the waters above the continental shelf and the Arctic waters between the islands of archipelagos. These areas, known as the Arctic ring of life, have high level of biological productivity in comparison to the deep waters of the High Arctic. This is particularly true of the seas surrounding Svalbard, which are among the most productive seas in the entire Arctic Ocean. Polar bears are therefore found primarily along the perimeter of the ice pack, rather than in the Polar Basin closer to the North Pole, where the density of seals is low. The polar bear is classified as a vulnerable species, with several subpopulations in decline. For decades, largescale hunting raised international concern for the future of the species, but populations rebounded after controls and quotas began to take effect. For thousands of years, the polar bear has been a key figure in the material, spiritual, and cultural life of several Arctic indigenous people. Polar bears are found throughout Svalbard, including on the extensive sea ice cover south of the archipelago. Occasionally, they drift widely on sea ice, and there have been anecdotal sightings of polar bears as far south as the north Norwegian coast of Finnmark. It is difficult to estimate the global population of polar bears, but a working estimate is about 20,000 to 25,000. Modern methods of tracking polar bear populations have been implemented only since the mid-1980s and are expensive to apply consistently over a large area. The most accurate counts require flying in a helicopter to detect polar bears, shooting tranquiliser darts to sedate them, and then following the tagged bears via satellite. Young polar bears are curious and come often close to vessels (page 141). The photographs above shows a polar bear that has recently caught a seal, with gulls waiting for the leftovers. 140 Svalbard Life

3 Marine mammals: Ringed seal Marine mammals: Bearded seal months, they give birth to a single pup in March to April, on ice floes or shore-fast ice. The pups are weaned after 1 month, during which period they build up a thick layer of blubber. In that time, they are vulnerable to attacks by polar bears, which break through the roofs of the cavities in which the pups rest. Also during the pupping season, Arctic foxes and glaucous gulls take ringed seal pups born outside dens. Killer whales and occasionally walruses prey upon pups in the water. Ringed seals are normally solitary animals and when hauled out on ice they keep a distance of hundreds of metres from each other. Feeding is usually also a solitary activity and their preferred prey includes shrimps, polar cod, and herring. When feeding, ringed seals may dive to depths of metres. Ringed seals live for about years shallow coastal areas less than 200 metres in depth. However, pups up to 1 year in age will venture much deeper and dive down to depths of 450 metres. Bearded seals give birth in the spring. Around Svalbard, seal pupping occurs in May. The pups are born on small, drifting ice floes in shallow waters and at birth they usually weigh in the range of kilograms. They enter the water only hours after they are born, and quickly become proficient divers. The mothers care for their pups for days, during which time the pups grow at an average rate of 3.3 kilograms per day. During that time, the pups consume an average of 8 litres of milk per day. By the time they are weaned, the pups have increased their weight to about 100 kilograms. If one imagines a weight gain of 3.3 kilograms based upon only 8 litres of milk it will quickly become apparent that the milk is actually liquid fat! Just before the pups are weaned, a new mating cycle takes place. Female bearded seals ovulate at the end of their lactation period, but remain close to their pups, Ringed seals are the most common and widely distrib- pack ice. The seals maintain a breathing hole in the ice, ready to defend them if necessary. During the mating uted seals in the Arctic, and can be found throughout allowing them to use ice habitats that other seals can- The bearded seal is a medium-sized seal species found adult per ice floe. Bearded seals on drifting ice floes season, male seals will sing, emitting a long-drawn-out the Northern Hemisphere s circumpolar oceans, where not access. Their small front flippers have claws that are within and near to the Arctic Ocean. Its common name can cover great distances, and their migration is thus call that ends in a sort of moan or sigh. This sound may they feed on polar cod and a variety of planktonic crus- more than 2 centimetre thick and are used to keep the is derived from its most characteristic feature, name- dependent on the season and distribution of ice floes. attract females and/or may be used by the males to pro- taceans. Different populations have different names and breathing holes open in up to 2 metres thick ice. Ringed ly conspicuous and very abundant whiskers. When dry, Bearded seals follow ice further south during the winter claim their territory or their readiness to breed. Bearded exhibit some variation in their behaviour and appear- seals prefer to rest on ice floes and in the summer they the whiskers curl very elegantly, giving bearded seals a and further north during the summer. By riding drifting seals are promiscuous and have more than one mate ance. Ringed seals derive their name from the light-col- move farther north to denser ice. They can be found dashing look. Adults are greyish-brown in colour, and ice floes, they gain access to shallow waters, in which during each breeding season. Males leave after mating oured, circular patterns that appear on their darker grey throughout the marginal ice zone around Svalbard, par- darker on their back. Occasionally, their face and neck they feed. Bearded seals rarely choose to rest on land. and do not provide any care for their pups. Due to their backs. Some of these markings are so dense that they ticularly in the south-western Barents Sea. are reddish-brown. Bearded seal pups are born with a However, in summertime, when ice floes are sparse, solitary nature, bearded seals do not establish long-term take on the appearance of splattered paint. greyish-brown natal fur with scattered patches of white they have been known to haul out on land and gravel bonds with mating partners. Female ringed seals reach sexual maturity at 4 years, on their back and head. Bearded seals grow to about beaches. The ringed seal is the smallest and most common seal in whereas males do not reach maturity until they are metres in length and weigh in the range of Like many Arctic mammals, bearded seals employ a the Arctic, with a small head, a short cat-like snout, and years old. The mating season starts in late April, when kilograms. Both sexes are about the same size. Bearded seals are a primary food source for the Inuit of reproductive strategy known as delayed implantation. a plump body. Their coat is dark with silver rings on the males roam the ice in search of a mate. Paired seals may the Arctic coasts and for polar bears. The seals mainly This means that the first stages of the embryo are not back and sides, and they have a silver belly. Depending spend several days together before mating, after which Bearded seals prefer shallow Arctic waters less than 200 find food at the bottom of the ocean, where they feed implanted for 2 months after fertilisation. Thus, a seal s on subspecies and conditions, the size of adult ringed the male will search for another mate. During the spring metres in depth. They also prefer areas with heavy ice on a variety of small prey, including clams, squids, and total gestation period is around 11 months, although its seals can be in the range of centimetres. breeding season, females construct dens within the thick floes or pack ice, where they can haul themselves out fish; their whiskers serve as feelers in the soft-bottom active gestation period is only 9 months. Ringed seals are commonly associated with ice floes and ice, in which they give birth. After a gestation period of 9 onto the surface. They generally segregate, with one sediments. Adult seals tend not to dive deep, but favour 142 Svalbard Life Svalbard Life 143

4 Marine mammals: Walrus The walrus is a large marine mammal with a discontinuous distribution around the North Pole and subarctic seas. Prominent tusks, whiskers, and bulkiness make adult walruses easily recognisable. Around Svalbard, adult males can weigh more than 1000 kilograms. The blubber layer beneath their extremely thick, dense skin can be up to 15 centimetres thick. Walruses live for about years. The males reach sexual maturity as early as 7 years, but do not typically mate until they are fully developed, at around 15 years of age. Calves are born during the spring migration, from April to June. They weigh in the range of kilograms at birth and are able to swim straight away. The mothers nurse for more than 1 year before weaning their offspring, but the young can spend between 3 and 5 years with their mothers. Young walruses are deep brown in colour and grow paler and more cinnamon-coloured as they age. Old males, in particular, become almost pink in colour. Walruses are social animals and live mostly in shallow waters above the continental shelves, spending significant amounts of their lives on sea ice. They have a diverse and opportunistic diet, feeding on a wide variety of marine organisms. However, they especially prefer clams, which they forage for by grazing along the sea bottom, using their tusks to disturb the layers in order find hidden food. The walrus has played a prominent role in the cultures of the people of the Arctic, who have hunted the species for its meat, fat, skin, tusks, and bones. During the 18th and 19th centuries, walruses were widely hunted and killed in Svalbard for their ivory, skins, and meat. The Atlantic walrus was almost eradicated by commercial harvesting. Good estimates of walrus numbers are difficult to obtain, but the worldwide population is probably below 20,000. The population of walruses has rebounded somewhat since commercial hunting ceased. The populations in the North Atlantic and Laptev Sea remain fragmented and at low levels compared to the time before human interference. Single or small groups of walruses can be seen in the northern regions of Svalbard, often near sea ice in relatively shallow waters, such as the protected, moraineridge island of Moffen, north of Svalbard. Svalbard Life 145

5 Marine mammals: Minke whale Marine mammals: Fin whale By the end of the 1930s, minke whales were targeted by The fin whale is a filter feeder, and feeds on small the coastal whaling operations of many coastal states. schooling fish, squid, and crustaceans. It feeds by open- By the early 1970s, following the overhunting of larger ing its jaws while swimming at a relatively high speed whales, minke whales became an even more attractive (more than 10 kilometres per hour, which causes it to target. Hunting continued until the general moratorium take in up to 70 cubic metres of water in one gulp. It on whaling was introduced in Although Norway then closes its jaws and pushes the water back out of initially supported the moratorium, an objection was its mouth through its baleen, which allows the water to placed with the International Whaling Commission. leave but traps the prey. Each gulp provides a whale with Norwegian commercial hunting was resumed in approximately 10 kilograms of plankton. One whale can Currently, the country s annual quota ranges between consume up to 1800 kilograms of food per day, leading a few hundred to just over 1000 whales, but often the scientists to conclude that the whale spends about 3 quotas are not filled. The catch is exclusively for human hours per day feeding to meet its energy requirements. consumption. Much of the annual quota is taken in late spring and early summer in waters around Svalbard. Like all other large whales, the fin whale was heav- Those who wish to experience what life in the Arctic ily hunted during the 20th century. The International implies and do not have ethical impediments should Whaling Commission (IWC) has issued a moratorium use the opportunity to eat what has been one of the on commercial hunting of this whale, although a few most common types of food for the Norwegian popula- countries, including Iceland and Japan, have resumed tion: minke whale.those that travel to Svalbard by ship hunting. Greenlanders also hunt the species under the should look out for whales that blow, particularly dur- Aboriginal Subsistence Whaling provisions of the IWC. ing whale weather, i.e. when the sea is comparatively Estimates suggest that the population of fin whales smooth. The fin whale is the second largest animal on earth after minutes. On their terminal (last) dive before descending, worldwide is around 100,000. n The minke whale or lesser rorqual (which takes its name calves measure in the range of metres at birth. the blue whale, and can grow to more than 27 metres they arch their back high out of the water. Thereafter, from the French rorqual, which in turn derives from The newborn whales nurse for at least 5 months and in in length and weigh almost 74 tonnes. The long and they dive to depths of up to 470 metres when feeding or the Norwegian word røyrkval, meaning furrow whale ) some cases up to 10 months. Calving is thought to occur slender body of the fin whale is brownish-grey with only 100 metres when resting or travelling. is the most abundant of all baleen whale species and is every second year. a paler underside. The fin whale is found in all of the found in both the Arctic Ocean and the Antarctic Ocean. world s major oceans, from polar seas to tropical waters, The fin whale is one of the fastest whales and can sus- They are seasonal feeders, carnivores, and sieve their The minke whale has a black-grey colour and is dis- and often it can be sighted around Svalbard. It is absent tain speeds of 37 kilometres per hour, and bursts in food through their baleen. They filter out plankton, krill, tinguished from other whales by having a white band only from waters close to the ice pack. Its food consists excess of 40 kilometres per hour have been recorded, and small fish, and even chase schools of capelin. Minke on each flipper. The upper part of the body is usually of small schooling fish (e.g. capelin), squid, and crusta- earning the fin whale the nickname the greyhound whales are the second smallest of the baleen whales. black or dark-grey and the lower part is white. Most of ceans, including copepods and krill. of the sea. Fin whales are more gregarious than other Upon reaching sexual maturity at 6 8 years of age, both a minke whale s back, including its dorsal fin and blow- rorquals, and often live in groups of 6 10 mammals. males and females measure about 7 metres in length. hole, is visible when it surfaces to breathe. The whale The fin whale is usually distinguished by its tall, vertical Female fin whales reach sexual maturity at 6 12 years Estimates of maximum length vary from about 9 me- breathes 3 5 times at short intervals, before deep-div- spout, long back, prominent dorsal fin, and asymmetri- of age, when their lengths reach metres, and they tres to 11 metres. Both sexes typically weigh 4 5 tons at ing for 2 20 minutes. The spout of the minke whale is cal coloration. Full physical maturity is attained between reproduce every 2 3 years. Mating occurs in temperate, maturity, and their maximum weight may be as much comparatively low, almost an inconspicuous stream that the ages of 25 years and 30 years. Fin whales live up to low-latitude seas during the winter, followed by a ges- as 14 tons. Minke whales typically live for years. rises to 2 metres above the water surface. A pronounced about 100 years, although specimens have been found tation period of months. A newborn calf weans In the north-eastern Atlantic, the total population of arching of the back precedes deep dives. The maximum with an estimated age of years. When feed- from its mother at 6 7 months of age, when it is minke whales is estimated to be approximately 103,000. swimming speed of minke whales has been estimated at ing, they will blow 5 7 times in quick succession, but metres in length, and accompanies its mother to the The gestation period for minke whales is 10 months, and 38 kilometres per hour. while travelling or resting they blow once every 1 or 2 summer feeding grounds. 146 Svalbard Life Svalbard Life 147

6 Terrestrial mammals Landscapes in the High Arctic are determined by glaciation, permafrost and a harsh climate. Where permafrost is continuous, the ground is frozen to several hundred metres. Only in summer does the top 1 metre melt sufficiently to create poorly drained marshy soils with a certain amount of dry terrain. Arctic plants have to adapt to the harsh conditions of winter when there is intense frost, yet they also need to endure high summer temperatures that within the low-lying vegetation can rise to 30 C. Mosses and lichens are frequent. There is a scarcity of littoral plants, mainly due to sea-ice scouring. Inland, behind the shores, there is a profusion of special, small plants. There are some 165 species of highly adapted flowering plants in Svalbard. The growing season is very short, and therefore the plants need to grow, flower, and produce seeds within a period of just a few weeks. Despite difficult conditions, the flora can appear almost luxuriant during summer, with welcome splashes of colour that brighten the apparently barren landscapes. The purple patches of mountain saxifrage and the dark-green, almost fluorescent patches of vegetation below bird colonies (fertilised by guano) please the eyes of visitors that have started to become accustomed to the stony and icy deserts of Svalbard. Svalbard is an almost treeless region, but a handful of species, such as the Arctic willow and dwarf birch, survive by virtue of being small and stunted, often only ankle-high. A person from central Europe may find that the woods of northern Norway are mainly composed of bushes, whereas in Svalbard there are groups of shrubs. A few of the most common mammals that a visitor to Svalbard may encounter are present here. The patterns in the photograph are the footprints of polar bears at the end of the snowy season. n 148 Svalbard Life

7 Terrestrial mammals: Arctic fox and alpine areas, such as Iceland and mainland alpine Scandinavia. The conservation status of the species is good, with the exception of the Scandinavian mainland population. The Arctic fox lives in one of the planet s frigid zones. Among its adaptations for survival in the cold are its deep, thick fur, a system of counter-current heat exchange in the circulation in the paws, to retain core temperature, and a good supply of body fat. The Arctic fox has a low surface area to volume ratio, as is evident from its generally rounded body shape, short nose and legs, and short, thick ears. Since less of its surface area is exposed to the Arctic cold, less heat escapes the body. Its furry paws allow it to walk on ice in search of food. The Arctic fox has a keen sense of hearing and can precisely locate the position of its prey under the snow. When it finds prey, it pounces and punches through the snow to catch its victim. The fox s fur changes colour with the seasons: in the winter it is white, to blend in with snow, while in the summer it is brown. Foxes tend to form monogamous pairs in the breeding season. Litters are born in the early summer and the parents raise the young in a large den. Such dens can be complex underground networks, housing many generations of foxes. Both parents help to raise their young. Young from a previous year s litter may stay with the parents to help rear younger siblings. The kits are initially brownish in colour and they turn white as they grow older. The Arctic fox is a small fox that is native to Arctic regions and is common throughout the Arctic tundra. The fox ranges between 70 centimetres and 110 centimetres in length. On average, males weigh 3.5 kilograms and females weigh 2.9 kilograms. The Arctic fox has a circumpolar range, meaning that it is found throughout the Arctic, including the periphery of Greenland, Russia, Canada, Alaska, and Svalbard, as well as in subarctic In Svalbard, Arctic foxes generally eat any small animal, carcasses, or eggs that it can find. During April and May, they also prey on ringed sea pups when the young animals are confined to a snow cavity and relatively helpless. Fish beneath the ice can also be part of the foxes diet. Arctic foxes also consume berries and seaweed, and are thus omnivores. If there is an overabundance of hunted food, the fox will bury what its family cannot eat. When its normal prey is scarce, the Arctic fox eat whatever they have buried earlier, scavenge leftovers and consume even faeces of larger predators, such as the polar bear. 150 Svalbard Life

8 Terrestrial mammals: Svalbard reindeer months of August and September. Males shed their antlers early in the winter. By contrast, the growth of female reindeers antlers begins in June, and the antlers are usually shed after a full year. Svalbard reindeer have a varied diet and will eat almost any type of vegetation. During winter, the reindeer concentrate on ridges, mountain slopes, plateaus, and other areas with comparatively less snow. During summer, they are found in areas where there is lush vegetation, often in valleys and on lowland plains. They spend most of their time feeding in the summer months and accumulate significant amounts of fat. The fat reserves are used during winter, when less vegetation is available and is of lower quality. Svalbard reindeer rarely occur in groups of more than 3 5 individuals, except during the rut in late autumn. The species has undergone several adaptations that help it to survive the variable climatic conditions and high degree of seasonality in Svalbard. For example, the animals exhibit very sedentary behaviour, which reduces their energy demands, and they have a well-developed ability to use their own reserves (both fat and muscle tissue) when access to food is very restricted during the winter. In addition, due to their fur, they are well insulated against the winter cold. The Svalbard reindeer is found only on Svalbard. It is very small compared to other subspecies of reindeer. It is approximately centimetres in length, and weighs around kilograms in spring and kilograms in autumn. Svalbard reindeer may have a shoulder height as low as 80 centimetres. They are short-legged and have relatively short, round heads. Their coat is brown on the back and light on the belly. During winter, the coat is a lighter shade than during summer and often appears either light grey or yellowwhite. The thick coat makes even starved animals appear fat in the winter and contributes to the short-legged appearance. The males develop heavy antlers during the period April July and shed their velvet during the Svalbard reindeer mate in October. The males gather a harem of up to 10 females. The females are pregnant for about 7 months and give birth to a single calf in June. The calf suckles for about 3 months, growing rapidly during this time. Calves weigh about 3 kilograms at birth, but can gain 7 8 kilograms per month during their first summer. When conditions are favourable, females have their first calf at 2 years of age. The lifespan of Svalbard reindeer is normally about 10 years. The variable climatic conditions in Svalbard induce large amounts of variation in both survival rates and reproductive rates from year to year. It takes a big stretch of imagination to link the Svalbard reindeer shown in the photographs to the fictional Rudolph the Red-Nosed Reindeer, with a glowing red nose, and his fellow chubby, short-legged reindeer pulling Santa s sleigh on Christmas Eve. n Svalbard Life 153